Most people know they need to lose weight for a variety of health reasons if they’re obese—that is, their body mass index (BMI, a ratio of weight to height) is 30 or more. But the health risks tied to weight aren’t a simple matter of crossing a line into obesity. A new study shows that the heavier you are, the greater your health risks, beginning in the overweight category, with a BMI of 25-29.9.

Doctors have actually defined three categories of obesity: obesity 1, with a BMI of 30-34.9; obesity 2 (35-39.9); and extreme obesity (40). A research team supported by NIH set out to look at the relationship of these different levels of obesity to mortality and heart disease.

The researchers studied data from over 90,000 women between 50 and 79 years old over a 7-year period. They found that the risk for mortality was almost 25% higher for women in the obesity 1 category than for those in the normal range, about 50% higher for obesity 2, and almost 75% higher for those with extreme obesity. The risk of heart disease was strongly related to weight as well, with a higher risk beginning for people in the overweight range. Severely obese women also had higher rates of diabetes and high blood pressure than women in the lower weight classes.

The rates of extreme obesity differed with race and ethnicity, ranging from 1% among Asian and Pacific Islanders to 10% among black women. However, once the women’s weights were taken into account, the mortality and heart disease rates didn’t differ by race or ethnicity.

This study shows that the more overweight you are, the greater your health risks. It’s important to maintain a healthy weight and to get appropriate treatment if you struggle with obesity.

Some studies have suggested that an urban community’s design can affect how heavy its residents are. A new study suggests that community features may also influence obesity in rural neighborhoods.

Researchers funded by NIH surveyed over 2,500 people by telephone in 13 communities in rural regions of Missouri, Tennessee and Arkansas. They were asked their height and weight and about their diets and physical activity levels, along with a series of questions about their communities.

Those who said they were far from a recreational facility or a walking or biking trail were more likely to be obese. Also more likely to be obese were those who said they weren’t within walking distance of local destinations like a library, grocery store or post office. Feeling unsafe from traffic and crime were both associated with obesity. People who perceived their community as unpleasant were more likely to be obese as well.

Like many other studies, this one found that people who got little physical activity and had high amounts of fat in their diets were more likely to be obese. The availability and quality of fresh fruits and vegetables, however, had no link
with obesity.

This study suggests, but doesn’t prove, that rural neighborhoods can affect obesity by influencing how much physical activity people get. Obese people may be more likely to choose to live in places with fewer opportunities for physical activity in the first place. They may also be less aware of the opportunities around them. Further studies will reveal whether the way a community is designed can really affect how much the people who live there weigh.

A free after-school program to help young people interpret the media messages they receive every day to make healthier choices about food and physical activity. Fun, interactive activities teach critical thinking skills that will help young people make smart decisions about what they eat and how they spend their time.